Biomass treatment for hyperthermal hydrocatalytic conversion

ABSTRACT

A selective removal of metal and its anion species that are detrimental to subsequent hydrothermal hydrocatalytic conversion from the biomass feed prior to carrying out catalytic hydrogenation/hydrogenolysis/hydrodeoxygenation of the biomass in a manner that does not reduce the effectiveness of the hydrothermal hydrocatalytic treatment while minimizing the amount of water used in the process is provided.

The present application is a divisional of U.S. Non-Provisional Ser. No.14/574,689, filed Jun. 18, 2015 which claims the benefit of U.S.Provisional Patent Application Ser. No. 61/917,445, filed Dec. 18, 2013,the entire disclosures of which are hereby incorporated by reference.

FIELD OF THE INVENTION

The invention relates to treatment of biomass for the hydrothermalhydrocatalytic treatment in the production of higher hydrocarbonssuitable for use in transportation fuels and industrial chemicals frombiomass. More specifically, the invention relates to removal ofdetrimental species from the biomass for an effective biomasshydrothermal hydrocatalytic conversion.

BACKGROUND OF THE INVENTION

A significant amount of attention has been placed on developing newtechnologies for providing energy from resources other than fossilfuels. Biomass is a resource that shows promise as a fossil fuelalternative. As opposed to fossil fuel, biomass is also renewable.

Biomass may be useful as a source of renewable fuels. One type ofbiomass is plant biomass. Plant biomass is the most abundant source ofcarbohydrate in the world due to the lignocellulosic materials composingthe cell walls in higher plants. Plant cell walls are divided into twosections, primary cell walls and secondary cell walls. The primary cellwall provides structure for expanding cells and is composed of threemajor polysaccharides (cellulose, pectin, and hemicellulose) and onegroup of glycoproteins. The secondary cell wall, which is produced afterthe cell has finished growing, also contains polysaccharides and isstrengthened through polymeric lignin covalently cross-linked tohemicellulose. Hemicellulose and pectin are typically found inabundance, but cellulose is the predominant polysaccharide and the mostabundant source of carbohydrates. However, production of fuel fromcellulose poses a difficult technical problem. Some of the factors forthis difficulty are the physical density of lignocelluloses (like wood)that can make penetration of the biomass structure of lignocelluloseswith chemicals difficult and the chemical complexity of lignocellulosesthat lead to difficulty in breaking down the long chain polymericstructure of cellulose into carbohydrates that can be used to producefuel. Another factor for this difficulty is the nitrogen compounds andsulfur compounds contained in the biomass. The nitrogen and sulfurcompounds contained in the biomass can poison catalysts used insubsequent processing.

Most transportation vehicles require high power density provided byinternal combustion and/or propulsion engines. These engines requireclean burning fuels which are generally in liquid form or, to a lesserextent, compressed gases. Liquid fuels are more portable due to theirhigh energy density and their ability to be pumped, which makes handlingeasier.

Currently, bio-based feedstocks such as biomass provide the onlyrenewable alternative for liquid transportation fuel. Unfortunately, theprogress in developing new technologies for producing liquid biofuelshas been slow in developing, especially for liquid fuel products thatfit within the current infrastructure. Although a variety of fuels canbe produced from biomass resources, such as ethanol, methanol, andvegetable oil, and gaseous fuels, such as hydrogen and methane, thesefuels require either new distribution technologies and/or combustiontechnologies appropriate for their characteristics. The production ofsome of these fuels also tends to be expensive and raise questions withrespect to their net carbon savings. There is a need to directly processbiomass into liquid fuels, amenable to existing infrastructure.

Processing of biomass as feeds is challenged by the need to directlycouple biomass hydrolysis to release sugars, and catalytichydrogenation/hydrogenolysis/hydrodeoxygenation of the sugar, to preventdecomposition to heavy ends (caramel, or tars). Further, it is achallenge to minimize generation of waste products that may requiretreating before disposal and/or catalyst deactivation by poisons.

SUMMARY OF THE INVENTION

It was found desirable to remove detrimental species from the biomassfeed prior to carrying out catalytichydrogenation/hydrogenolysis/hydrodeoxygenation of the biomass in amanner that does not reduce the effectiveness of the hydrothermalhydrocatalytic treatment while minimizing the amount of water used inthe process.

In one embodiment, a method for selective removal of detrimental metalsand their anion species from a cellulosic biomass solids is provided,said method comprising a plurality of vessels:

-   -   a. providing each of said vessels with one of detrimental        species-containing cellulosic biomass solids;    -   b. introducing a first dispersed or semi-continuous liquid phase        comprising an acidic solution having a pH of at most 4 from an        inlet into a first vessel of said plurality of vessel wherein        the cellulosic biomass solids in the first vessel is contacted        by said first dispersed or semi-continuous liquid phase and        first continuous gas phase at a temperature in the range of        about 0° C. to about 60° C. wherein the flux of the first liquid        phase is at least 1 kg/(m² s);    -   c. repeating step (b) for a second vessel of said plurality of        vessels;    -   d. introducing a second dispersed or semi-continuous liquid        phase comprising an aqueous solution having a pH of at least 5        from an inlet into said first vessel of said plurality of        vessels treated according to step (b) wherein said acidic        solution-treated cellulosic biomass solids in the first vessel        is contacted by said second dispersed or semi-continuous liquid        phase and second continuous gas phase wherein the flux of the        second liquid phase is at least 1 kg/(m² s) and discharging an        acidic effluent;    -   e. repeating step (d) for the second vessel of said plurality of        vessels treated according to step (c);    -   f. transferring at least a portion of the biomass treated        according to steps (d) and (e) to a digestion and/or reaction        vessel;    -   g. wherein at least 2 of the vessels are undergoing at least one        of the steps (b) through (f) at the same time; and    -   h. wherein the amount of the total discharged acidic effluent        from the plurality of the vessels is in the range of from about        3 parts to about 0.5 parts relative to about 1 part of        detrimental species-containing cellulosic biomass solids (dry        basis).

In another embodiment, a method for selective removal of detrimentalmetals and their anion species from a cellulosic biomass solids isprovided, said method comprising a plurality of vessels:

-   -   a. providing each of said vessels with one of detrimental        species-containing cellulosic biomass solids;    -   b. introducing a first dispersed or semi-continuous liquid phase        comprising an acidic solution having a pH of at most 4 from an        inlet into a first vessel of said plurality of vessel wherein        the cellulosic biomass solids in the first vessel is contacted        by said first dispersed or semi-continuous liquid phase and        first continuous gas phase at a temperature in the range of        about 0° C. to about 60° C. wherein the flux of the first liquid        phase is at least 1 kg/(m² s);    -   c. repeating step (b) for a second vessel of said plurality of        vessels;    -   d. introducing a second dispersed or semi-continuous liquid        phase comprising an aqueous solution having a pH of at least 5        from an inlet into said first vessel of said plurality of        vessels treated according to step (b) wherein said acidic        solution-treated cellulosic biomass solids in the first vessel        is contacted by said second dispersed or semi-continuous liquid        phase and second continuous gas phase wherein the flux of the        second liquid phase is at least 1 kg/(m² s) and discharging an        acidic effluent;    -   e. repeating step (d) for the second vessel of said plurality of        vessels treated according to step (c);    -   f. introducing a third dispersed or semi-continuous liquid phase        comprising a base solution having a pH of greater than 9 from an        inlet into said first vessel of said plurality of vessels        treated according to step (d)) wherein said aqueous        solution-treated cellulosic biomass solids in the first vessel        is contacted by said third dispersed or semi-continuous liquid        phase and third continuous gas phase wherein the flux of the        third liquid phase is at least 1 kg/(m² s) and discharging an        aqueous effluent;    -   g. repeating step (f) for a second vessel of said plurality of        vessels treated according to step (e);    -   h. introducing a fourth dispersed or semi-continuous liquid        phase comprising an aqueous solution having a pH of at most 8        from an inlet into said first vessel of said plurality of        vessels treated according to step (f) wherein said base        solution-treated cellulosic biomass solids in the first vessel        is contacted by said fourth dispersed or semi-continuous liquid        phase and fourth continuous gas phase wherein the flux of the        fourth liquid phase is at least 1 kg/(m² s) and discharging a        basic effluent;    -   i. repeating step (h) for the second vessel of said plurality of        vessels treated according to step (g);    -   j. transferring at least a portion of the biomass treated        according to steps (h) and (i) to a digestion and/or reaction        vessel;    -   k. wherein at least 2 of the vessels are undergoing at least one        of the steps (b) through (j) at the same time; and    -   l. wherein the amount of the total discharged acidic effluent        and basic effluent from the plurality of vessels is in the range        of from about 3 parts to about 0.5 parts relative to about 1        part of detrimental species-containing cellulosic biomass solids        (dry basis).

In yet another embodiment, a method for selective removal of detrimentalmetals and their anion species from cellulosic biomass solids, saidmethod comprising a plurality of vessels:

-   -   a. providing each of said vessels with one of detrimental        species-containing cellulosic biomass solids;    -   b. introducing a first dispersed or semi-continuous liquid phase        comprising a base solution having a pH of greater than 9 from an        inlet into a first vessel of said plurality of vessel wherein        the cellulosic biomass solids in the first vessel is contacted        by said first dispersed or semi-continuous liquid phase and        first continuous gas phase at a temperature in the range of        about 0° C. to about 60° C. wherein the flux of the first liquid        phase is at least 1 kg/(m² s);    -   c. repeating step (b) for a second vessel of said plurality of        vessels;    -   d. introducing a second dispersed or semi-continuous liquid        phase comprising an aqueous solution having a pH of at most 8        from an inlet into said first vessel of said plurality of        vessels treated according to step (b) wherein said base        solution-treated cellulosic biomass solids in the first vessel        is contacted by said second dispersed or semi-continuous liquid        phase and second continuous gas phase wherein the flux of the        second liquid phase is at least 1 kg/(m² s) and discharging a        basic effluent;    -   e. repeating step (d) for the second vessel of said plurality of        vessels treated according to step (c);    -   f. introducing a third t dispersed or semi-continuous liquid        phase comprising an acidic solution having a pH of at most 4        from an inlet into a first vessel of said plurality of vessel        treated according to step (d) wherein the cellulosic biomass        solids in the first vessel is contacted by said third dispersed        or semi-continuous liquid phase and third continuous gas phase        at a temperature in the range of about 0° C. to about 60° C.        wherein the flux of the first liquid phase is at least 1 kg/(m²        s);    -   g. repeating step (f) for a second vessel of said plurality of        vessels treated according to step (e);    -   h. introducing a fourth dispersed or semi-continuous liquid        phase comprising an aqueous solution having a pH of at least 5        from an inlet into said first vessel of said plurality of        vessels treated according to step (f) wherein said acidic        solution-treated cellulosic biomass solids in the first vessel        is contacted by said fourth dispersed or semi-continuous liquid        phase and fourth continuous gas phase wherein the flux of the        fourth liquid phase is at least 1 kg/(m² s) and discharging an        acidic effluent;    -   i. repeating step (h) for the second vessel of said plurality of        vessels treated according to step (g);    -   j. transferring at least a portion of the biomass treated        according to steps (i) and (j) to a digestion and/or reaction        vessel;    -   k. wherein at least 2 of the vessels are undergoing at least one        of the steps (b) through (j) at the same time; and    -   l. wherein the amount of the total discharged acidic solution        and base solution from the plurality of vessels is in the range        of from about 3 parts to about 0.5 parts relative to about 1        part of detrimental species-containing cellulosic biomass solids        (dry basis).

In yet another embodiment, in the digestion and/or reaction zone of theabove methods, the treated cellulosic biomass is contacted with ahydrothermal hydrocatalytic catalyst in the presence of hydrogen and adigestion solvent thereby producing an intermediate oxygenated productstream comprising oxygenated hydrocarbons and water; and at least aportion of the water is separated and recycled to form at least aportion of the aqueous solution.

In yet another embodiment, in the digestion and/or reaction zone in theabove methods, the treated cellulosic biomass is contacted with ahydrothermal hydrocatalytic catalyst in the presence of hydrogen and adigestion solvent thereby producing an intermediate oxygenated productstream; at least a portion of the oxygenated intermediate product streamis converted to a hydrocarbon product stream comprising hydrocarbons andwater; and at least a portion of the water is separated and recycled toform at least a portion of the aqueous solution. The oxygenatedintermediate product steam may comprise oxygenated hydrocarbons andwater, and at least a portion of the water maybe separated and recycledto form at least a portion of the aqueous solution.

The features and advantages of the invention will be apparent to thoseskilled in the art. While numerous changes may be made by those skilledin the art, such changes are within the spirit of the invention.

BRIEF DESCRIPTION OF THE DRAWING

This drawing illustrates certain aspects of some of the embodiments ofthe invention, and should not be used to limit or define the invention.

FIG. 1 is a schematically illustrated block flow diagram of anembodiment of a process 100 of this invention.

FIG. 2 is a schematically illustrated block flow diagram of anembodiment of a process 200 of this invention.

DETAILED DESCRIPTION OF THE INVENTION

In one embodiment, the invention relates to selective removal ofdetrimental metals and their anions, such as chlorine, from detrimentalspecies-containing cellulosic biomass solids. Any suitable (e.g.,inexpensive and/or readily available) type of lignocellulosic biomasscan be used. Suitable lignocellulosic biomass can be, for example,selected from, but not limited to, wood, forestry residues, agriculturalresidues, herbaceous material, municipal solid wastes, pulp and papermill residues, and combinations thereof. Thus, in some embodiments, thebiomass can comprise, for example, corn stover, straw, bagasse,miscanthus, sorghum residue, switch grass, duckweed, bamboo, waterhyacinth, hardwood, hardwood chips, hardwood pulp, softwood, softwoodchips, softwood pulp, and/or combination of these feedstocks. Thebiomass can be chosen based upon a consideration such as, but notlimited to, cellulose and/or hemicelluloses content, lignin content,growing time/season, growing location/transportation cost, growingcosts, harvesting costs and the like. These cellulosic biomass solidscontain metal species and its corresponding anions such as Mg, Ca, Na, KFe, Mn, Cl, SO₄, PO₄, NO₃ that are detrimental to catalysts or equipmentused in the hydrothermal hydrocatalytic treatment of the biomass(“detrimental species”). Hence, it is desirable to at least in partremove these detrimental species from the cellulosic biomass solidsbefore the hydrothermal hydrocatalytic treatment of biomass.

The oxygenated hydrocarbons produced from the hydrothermalhydrocatalytic process are useful in the production of higherhydrocarbons suitable for use in transportation fuels and industrialchemicals from biomass. The higher hydrocarbons produced are useful informing transportation fuels, such as synthetic gasoline, diesel fuel,and jet fuel, as well as industrial chemicals. As used herein, the term“higher hydrocarbons” refers to hydrocarbons having an oxygen to carbonratio less than the oxygen to carbon ratio of at least one component ofthe biomass feedstock. As used herein the term “hydrocarbon” refers toan organic compound comprising primarily hydrogen and carbon atoms,which is also an unsubstituted hydrocarbon. In certain embodiments, thehydrocarbons of the invention also comprise heteroatoms (i.e., oxygensulfur, phosphorus, or nitrogen) and thus the term “hydrocarbon” mayalso include substituted hydrocarbons. As used herein, the term “solublecarbohydrates” refers to monosaccharides or polysaccharides that becomesolubilized in a digestion process.

Although the underlying chemistry is understood behind digestingcellulose and other complex carbohydrates and further transformingsimple carbohydrates into organic compounds reminiscent of those presentin fossil fuels, high-yield and energy-efficient digestion processessuitable for converting cellulosic biomass into fuel blends have yet tobe developed. In this regard, the most basic requirement associated withconverting cellulosic biomass into fuel blends using digestion and otherprocesses is that the energy input needed to bring about the conversionshould not be greater than the available energy output of the productfuel blends. Further the process should maximize product yield whileminimizing waste products. These basic requirements lead to a number ofsecondary issues that collectively present an immense engineeringchallenge that has not been solved heretofore.

Further, the removal of these detrimental species is complicated by thesensitivity of the catalysts for the hydrothermal hydrocatalytictreatment to the reaction conditions. Processing of biomass as feeds ischallenged by the need to directly couple biomass hydrolysis to releasesugars, and catalytic hydrogenation/hydrogenolysis/hydrodeoxygenation ofthe sugar, to prevent decomposition to heavy ends (caramel, or tars).For example, too much water from a wash process can dilute the reactionstream and require removal of larger amounts of water from the processand may further lead to stress on the catalyst used in the process.Further, removal of water at a later stage by thermally separating thewater will require a large amount of energy. It is also desirable torecycle the wash water to minimize or eliminate the need for other waterinputs to the process.

In further embodiment, the invention relates recycling the water used towash the biomass and to minimizing the amount of waste water generatedin the process. The invention balances the competing advantage ofselective removal of detrimental metal species and its anion, such aschlorine, from a detrimental species-containing cellulosic biomasssolids while not reducing the effectiveness of the hydrothermalhydrocatalytic treatment while minimizing the amount of water used inthe process. Applicants have found that washing the biomass with diluteacids (mild acidic conditions) at low temperature effectively removes atleast a portion of the detrimental species in the biomass withoutremoval of carbohydrates. However a large amount of water required toremove the detrimental species also hinders and/or creates more processwater that requires more water removal and disposals. The process of theinvention provides effective solutions to these problems.

It is also important in the wash process to prevent the hydrolysis ofwood and loss of carbohydrate to the wash effluent (or aqueous solutioneffluent). Thus it is preferable to maintain the treatment of thebiomass to at most about 60° C. The loss of carbohydrate is preferablyless than 10% by weight, more preferably less than 5% by weight, evenmore preferably less than 2% by weight based on the carbohydratespresent in the biomass (dry basis).

Prior to treatment, the untreated biomass can be reduced in size (e.g.,chopping, crushing or debarking) to a convenient size and certainquality that aids in moving the biomass or mixing and impregnating thechemicals from digestive solvent. Thus, in some embodiments, providingbiomass can comprise harvesting a lignocelluloses-containing plant suchas, for example, a hardwood or softwood tree. The tree can be subjectedto debarking, chopping to wood chips of desirable thickness, and washingto remove any residual soil, dirt and the like.

It is preferable to render the biomass feed (wood chips or other) freeof entrained air, and densified to insure the feedstock will sink inwater or solvent, vs. float (pre-conditioning). Floating can occur ifthe feed is allowed to dry during storage, upon which air may enterpores and be transported into the process.

Densification via impregnation with water or solvent may be effected bysoaking in water or solvent. Pressurization of the water or solvent willforce liquid into pores. One of the most effective ways to drive gas(air or non-condensibles) out of the pore of the biomass is to contactthe biomass with solvent vapor, most preferable water vapor or steam.

Typically, this is done by supplying low pressure steam (nominal 1-2atmospheres above ambient pressure) to the bottom of a storage bin, andallowing the steam or solvent vapor to travel upwards through the bin ofsolids, to drive out air or entrained gas. Contacting of water orsolvent vapor at a temperature above the biomass temperature results incondensation of liquid water or vapor in the pores of the biomass,driving gas out of the pores. This saturates and densifies the biomasssuch that it now has a density greater than water or solvent, andtherefore sinks when added to liquid water or solvent during the washprocess.

The time and duration of the steaming should be controlled such that thetemperature of the biomass does not exceed about 60 degrees centigradefor an extended period of time. Specifically, one can supply steam attemperatures above 100 degrees centigrade (the boiling point of water),to biomass initially at ambient temperature (below about 35 degreescentigrade), for a period of time such that the final temperature of thebiomass does not exceed about 60 degrees centigrade, or if temperatureabove 60 degree centigrade, the exposure at this temperature is limitedto less than 60 minutes, preferably less than 30 minutes, and mostpreferably less than about 10 minutes. By minimizing the exposure totemperatures above 60° C., hydrolysis and degradation of carbohydratecomponents is minimized, and loss of these components to the waterand/or acid and base wash process steps can be minimized to less than 5%of the carbohydrate portion of the biomass, most preferably less than1%.

In the process of the invention, a plurality of vessels that can be 2 ormore vessels are used in parallel. The plurality of vessels are used inparallel where at least 2 of the plurality of vessels are undergoing atleast one of the steps of the process at the same time. There may be nvessels where n can be any integer. In some embodiments, the number ofvessels may be an integer from 2 to 20, preferably 2 to 10. In someembodiment, the number of vessels maybe an integer from 3 to 6. Thevessel can be in any shape that include, for example, vertical,horizontal, incline, and may include bends, curves or u shape. Thevessel will further have at least one inlet and at least one outlet.Each vessel contains a top portion and a bottom portion.

The detrimental species-containing cellulosic biomass solids is provided(or introduced) in to a first (treatment) vessel. This process isrepeated for the second (treatment) vessel. This process can be repeatedfor 3, 4, 5, 6, 7, 8, 9, 10, or n vessels.

In one embodiment, an acidic solution having a pH of at most 4,preferably having a pH of at least 0, more preferably having a pH in therange of 0 to 3, may be introduced to the vessel containing thecellulosic biomass solids as a first dispersed or semi-continuous liquidphase at a temperature in the range of 0° C. to 60° C., preferably inthe range of 10° C. to 45° C., at a flux of at least 1 kg/(m² s),preferably at least 3 kg/(m² s), and contacted with the cellulosicbiomass solids in the presence of a first continuous gas phase,producing an acidic cellulosic biomass solids. The inlet may be the sameinlet as the biomass solids introduction or a separate, second inlet tothe treatment vessel. This step is carried out with the first vessel andrepeated for a second vessel. The step can be carried out to n number ofvessels, that may be third, fourth, fifth, sixth, seventh, eighth,ninth, tenth, etc. up to n vessels.

After the acidic solution introduction, an aqueous solution having a pHof at least 5 to at most 8 is introduced from an inlet as a seconddispersed or semi-continuous liquid phase at a temperature in the rangeof 0° C. to 60° C., preferably in the range of 10° C. to 45° C., at aflux of at least 1 kg/(m² s), preferably at least 3 kg/(m² s), andcontacted with the acidic cellulosic biomass solids in the first vesselin the presence of the second continuous gas phase producing treated (orwashed in such embodiment) cellulosic biomass solids having reduceddetrimental species content compared to the detrimentalspecies-containing cellulosic biomass solids and an acidic effluent. Theinlet may be the same inlet as the biomass solids introduction, theacidic solution inlet, or a separate, second or third inlet to thetreatment vessel. The acidic effluent and the treated cellulosic biomasssolids may be removed from the treatment vessel from the same outlet ora separate, second, outlet. This step is carried out with the firstvessel and repeated for a second vessel. The step can be carried out ton number of vessels, that may be third, fourth, fifth, sixth, seventh,eighth, ninth, tenth, etc. up to n vessels.

The acid wash is carried out so that the amount of the total acidiceffluent from the plurality of treatment vessels is in the range ofabout 3 parts to about 0.5 parts, preferably in the range of about 2parts to about 1 part relative to the cellulosic biomass solids (drybasis) charged to the treatment step, based on weight.

The acidic effluent is discharged until the pH is greater than 3,preferably greater than 4, more preferably at least 5, or until theamount of the acidic effluent exceeds the acidic solution introducedinto the vessel, and at least a portion of the subsequent aqueouseffluent is recycled at least one time through the first vessel. Atleast a portion of the aqueous effluent is recycled to produce acidicsolution and/or aqueous solution. For example, at least a first portionof the aqueous effluent is recycled to produce acidic solution, and atleast a second portion of the aqueous effluent is recycled as an aqueoussolution. The pH of at least a portion of the discharged aqueoussolution may be adjusted to a pH of at most 4 by adding an acid to thedischarged aqueous solution prior to recycling as a portion of theacidic solution.

The first dispersed or semi-continuous liquid phase is preferablyrecycled at least one time through the first vessel for step (b) andthrough the second vessel for step (c) to increase residence time fortreatment, to effect multiple passes through the biomass being treated.The second dispersed or semi-continuous liquid phase is preferablyrecycled at least one time through the first vessel for step (d) andthrough the second vessel for step (e) to increase residence time fortreatment, to effect multiple passes through the biomass being treated.

The pretreated cellulosic biomass solids is discharged from an outlet ofthe treatment vessel, then transferred to a digestion and/or reactionzone. This step is carried out with the first vessels and repeated for asecond vessel. The step can be carried out to n number of vessels, thatmay be third, fourth, fifth, sixth, seventh, eighth, ninth, tenth, etc.up to n vessels. The above steps may be carried out in parallel inmultiple vessels, each vessels undergoing at least one of the steps,thus increasing the efficiency of the wash process.

The step can be carried out to n number of vessels, that may be third,fourth, fifth, sixth, seventh, eighth, ninth, tenth, etc. up to nvessels as long as at least 2 of the vessels are undergoing at least oneof the steps at the same time.

In another embodiment, after the aqueous solution is introduced to thebiomass solids containing vessel, optionally a base solution having a pHof greater than 9, preferably having a pH of at most 13, more preferablyhaving a pH of at least 10, more preferably having a pH in the range of10 to 13, may be introduced to the vessel containing the washedcellulosic biomass solids as a third dispersed or semi-continuous liquidphase at a temperature in the range of 0° C. to 60° C., preferably inthe range of 10° C. to 45° C., at a flux of at least 1 kg/(m² s),preferably at least 3 kg/(m² s), and contacted with the cellulosicbiomass solids in the presence of a third continuous gas phase,producing a basic cellulosic biomass solids. The inlet may be the sameinlet as the biomass solids introduction or a separate, second, orthird, inlet to the treatment vessel. This step is carried out with thefirst vessel and repeated for a second vessel. The step can be carriedout to n number of vessels, that may be third, fourth, fifth, sixth,seventh, eighth, ninth, tenth, etc. up to n vessels.

After the base solution introduction, an aqueous solution having a pH ofat least 5 to at most 9 is introduced from an inlet as a fourthdispersed or semi-continuous liquid phase at a temperature in the rangeof 0° C. to 60° C., preferably in the range of 10° C. to 45° C., at aflux of at least 1 kg/(m² s), preferably at least 3 kg/(m² s), andcontacted with the basic cellulosic biomass solids in the first vesselin the presence of the fourth continuous gas phase producing treated (orbase washed in such embodiment) cellulosic biomass solids having reduceddetrimental species content compared to the detrimentalspecies-containing cellulosic and a basic effluent. The inlet may be thesame inlet as the biomass solids introduction, the acidic solutioninlet, the aqueous solution inlet, or a separate, second or third orfourth inlet to the treatment vessel. The basic effluent, the acidiceffluent, the aqueous effluent, and the treated cellulosic biomasssolids may be removed from the treatment vessel from the same outlet ora separate, second, third or fourth outlet. This step is carried outwith the first vessel and repeated for a second vessel. The step can becarried out to n number of vessels, that may be third, fourth, fifth,sixth, seventh, eighth, ninth, tenth, etc. up to n vessels.

The base wash is carried out so that the amount of the total acidiceffluent and basic effluent from the plurality of the treatment vesselsis in the range of about 3 parts to about 0.5 parts, preferably in therange of about 2 parts to about 1 part relative to the cellulosicbiomass solids (dry basis) charged to the treatment step, based onweight.

At least a portion of the aqueous effluent is recycled to produce acidicsolution, base solution, and/or aqueous solution. For example, at leasta first portion of the aqueous effluent is recycled to produce acidicsolution. At least a first portion of the second aqueous effluent isrecycled to produce base solution; and at least a second portion of thesecond aqueous effluent is recycled as an aqueous solution.

The basic effluent is discharged until the pH is less than 9, preferablyat most 8, or until the amount of the basic effluent exceeds the basicsolution introduced into the vessel, and at least a portion of thesubsequent aqueous effluent is recycled at least one time through thefirst vessel. At least a portion of the aqueous effluent is recycled toproduce base solution and/or aqueous solution. For example, at least afirst portion of the aqueous effluent is recycled to produce basesolution, and at least a second portion of the aqueous effluent isrecycled as an aqueous solution. The pH of at least a portion of thedischarged aqueous solution may be adjusted to a pH of greater than 9 byadding a base to the discharged aqueous solution prior to recycling as aportion of the base solution.

The third dispersed or semi-continuous liquid phase is preferablyrecycled at least one time through the first vessel for step (f) andthrough the second vessel for step (g) to increase residence time fortreatment, to effect multiple passes through the biomass being treated.The fourth dispersed or semi-continuous liquid phase is preferablyrecycled at least one time through the first vessel for step (h) andthrough the second vessel for step (i) to increase residence time fortreatment, to effect multiple passes through the biomass being treated.

The pretreated cellulosic biomass solids is discharged from an outlet ofthe treatment vessel, then transferred to a digestion and/or reactionzone. This step is carried out with the first vessel and repeated for asecond vessel. The step can be carried out to n number of vessels, thatmay be third, fourth, fifth, sixth, seventh, eighth, ninth, tenth, etc.up to n vessels.

The above steps may be carried out in parallel in multiple vessels, eachvessels undergoing at least one of the steps, thus increasing theefficiency of the wash process. The step can be carried out to n numberof vessels, that may be third, fourth, fifth, sixth, seventh, eighth,ninth, tenth, etc. up to n vessels as long as at least 2 of the vesselsare undergoing at least one of the steps at the same time.

In yet another embodiment, the order of the acid wash and the base washmay be reversed in a manner so that, a base solution (described above)is introduced first from an inlet as a first dispersed orsemi-continuous liquid phase at a flux of at least 1 kg/(m² s),preferably at least 3 kg/(m² s), and contacted with the cellulosicbiomass solids in the presence of a first continuous gas phase,producing a basic cellulosic biomass solids. Then, an aqueous solution(described above) is introduced from an inlet as a second dispersed orsemi-continuous liquid phase and contacted with the basic cellulosicbiomass solids in the first vessel in the presence of a secondcontinuous gas phase producing treated (or base washed in suchembodiment) cellulosic biomass solids having reduced detrimental speciescontent compared to the detrimental species-containing cellulosic and abasic effluent. An acidic solution (described above) is introduced tothe vessel containing the washed cellulosic biomass solids as a thirddispersed or semi-continuous liquid phase at a flux of at least 1 kg/(m²s), preferably at least 3 kg/(m² s), and contacted with the cellulosicbiomass solids in the presence of a third continuous gas phase,producing an acidic cellulosic biomass solids. Then, an aqueous solution(described above) is then introduced from an inlet as a fourth dispersedor semi-continuous liquid phase and contacted with the acidic cellulosicbiomass solids in the first vessel in the presence of a fourthcontinuous gas phase producing treated (or washed in such embodiment)cellulosic biomass solids having reduced detrimental species contentcompared to the detrimental species-containing cellulosic biomass solidsand an acidic effluent.

The combined amount of total acidic water effluent and basic watereffluent from the plurality of vessels is in the range of about 3 partsto about 0.5 parts relative to about 1 part of detrimentalspecies-containing cellulosic biomass solids (dry basis).

The basic effluent is discharged until the pH is less than 9, preferablyat most 8, or until the amount of the basic effluent exceeds the basicsolution introduced into the vessel, and at least a portion of thesubsequent aqueous effluent is recycled at least one time through thefirst vessel. At least a portion of the aqueous effluent is recycled toproduce base solution and/or aqueous solution. For example, at least afirst portion of the aqueous effluent is recycled to produce basesolution, and at least a second portion of the aqueous effluent isrecycled as an aqueous solution. The pH of at least a portion of thedischarged aqueous solution may be adjusted to a pH of greater than 9 byadding a base to the discharged aqueous solution prior to recycling as aportion of the base solution.

The acidic effluent is discharged until the pH is greater than 3,preferably greater than 4, more preferably at least 5, or until theamount of the acidic effluent exceeds the acidic solution introducedinto the vessel, and at least a portion of the subsequent aqueouseffluent is recycled at least one time through the first vessel. Atleast a portion of the aqueous effluent is recycled to produce acidicsolution and/or aqueous solution. For example, at least a first portionof the aqueous effluent is recycled to produce acidic solution, and atleast a second portion of the aqueous effluent is recycled as an aqueoussolution. The pH of at least a portion of the discharged aqueoussolution may be adjusted to a pH of at most 4 by adding an acid to thedischarged aqueous solution prior to recycling as a portion of theacidic solution.

The first dispersed or semi-continuous liquid phase is preferablyrecycled at least one time through the first vessel for step (b) andthrough the second vessel for step (c) to increase residence time fortreatment, to effect multiple passes through the biomass being treated.The second dispersed or semi-continuous liquid phase is preferablyrecycled at least one time through the first vessel for step (d) andthrough the second vessel for step (e) to increase residence time fortreatment, to effect multiple passes through the biomass being treated.The third dispersed or semi-continuous liquid phase is preferablyrecycled at least one time through the first vessel for step (f) andthrough the second vessel for step (g) to increase residence time fortreatment, to effect multiple passes through the biomass being treated.The fourth dispersed or semi-continuous liquid phase is preferablyrecycled at least one time through the first vessel for step (h) andthrough the second vessel for step (i) to increase residence time fortreatment, to effect multiple passes through the biomass being treated.

The pretreated cellulosic biomass solids is discharged from an outlet ofthe treatment vessel, then transferred to a digestion and/or reactionzone. This step is carried out with the first vessels and repeated for asecond vessel. The step can be carried out to n number of vessels, thatmay be third, fourth, fifth, sixth, seventh, eighth, ninth, tenth, etc.up to n vessels.

The above steps may be carried out in parallel in multiple vessels, eachvessels undergoing at least one of the steps, thus increasing theefficiency of the wash process. The step can be carried out to n numberof vessels, that may be third, fourth, fifth, sixth, seventh, eighth,ninth, tenth, etc. up to n vessels as long as at least 2 of the vesselsare undergoing at least one of the steps at the same time. The use ofrecycle treatment water and parallel treatment vessels, as described inthe present invention, is effective to produce an effluent separatedfrom the biomass which contains a maximum concentrations of thedetrimental removed components, in the restricted amounts of watertreatment allowed. The amounts of water prescribed will typicallycorrespond to the natural water content of the biomass feedstock,augmented by any water which can be made in process conversion stepssuch as reaction of biomass with hydrogen, with zero or minimal use ofadditional water from another source. The amount of additional waterrequired is thus restricted to less than 50% of the biomass feed (drybasis), and hence would represent less than a third of the typicalamount of additional water employed for similar processing in themanufacture of, for example, pulp used to make paper. Preferably, theamount of additional makeup water above the water naturally present inthe biomass feed, and made in the process, is zero.

The acidic solution may contain an inorganic acid or carboxylic acid(“collectively referred herein as “acids”). The inorganic acid may be,for example, sulfuric acid, phosphoric acid, hydrochloric acid, nitricacid or mixtures thereof. The acid content of the acidic solution ispreferably less than 10 wt % and at least 0.01 wt %. The inorganic acidis preferably present in an amount of 0.01 wt % to 2 wt %. If sulfuricacid is used, the sulfuric acid is preferably present in an amount of0.01 wt % to 1 wt %. If phosphoric acid is used, the phosphoric acid ispreferably present in an amount of 0.01 wt % to 2 wt %. If nitric acidis used, the nitric acid is preferably present in an amount of 0.01 wt %to 1 wt %. The carboxylic acid may be, for example, acetic acid,levulinic acid, lactic acid, formic acid, propionic acid, or mixturesthereof. The carboxylic acid is preferably present in an amount of 0.1wt % to 5 wt %. If acetic acid is used, the acetic acid is preferablypresent in an amount of 0.1 wt % to 2.5 wt %.

The base solution may contain an inorganic base such as, for example,KOH, NaOH and ammonia. The base content of the base solution ispreferably less than 5 Normal and at least 0.01 Normal. The baseconcentration is preferably from about 0.1 to about 5 Normal.

The gas phase may be air or any mixture of inert gases, such as nitrogenor argon, carbon dioxide, steam, or natural gas. Each of the continuousgas phase may be the same or different.

Preferably, the metal species content is reduced by at least 75%, atleast 80%, at least 85%, at least 90%, at least 95%, even at least 98%or essentially completely. More particularly the non-water solublemetals such as manganese is reduced by at least 20%, at least 30%, atleast 35%, at least 40%, at least 50%, at least 60%, at least 70%, atleast 75%, at least 80%, at least 90%, at least 95%, or essentiallycompletely. Preferably the anion content such as chlorine is alsoreduced by at least 50%, at least 55%, at least 60%, at least 75%, andeven at least 95%. The term “essentially completely” means the specie iscompletely removed within the detection limit or within statisticalsignificance or within measurement errors.

The inlet of the first and the second dispersed or semi-continuousliquid phase is generally at the top portion of the vessels.

After introduction of the aqueous solution, in any of the aboveembodiments, optionally an organic solvent solution may be introduced tothe vessel containing the washed cellulosic biomass solids, producing apretreated cellulosic biomass solids with organic solution, particularlyorganic solvent for the subsequent reaction processes. This step iscarried out with the first vessels and repeated for a second vessel. Thestep can be carried out to n number of vessels, that may be third,fourth, fifth, sixth, seventh, eighth, ninth, tenth, etc. up to nvessels.

At least a portion of the treated cellulosic biomass solids is providedto a digestion and/or reaction zone (collectively referred to as“hydrothermal hydrocatalytic reaction zone”) for further processing.This zone may be conducted in a single step or in multiple steps orvessels as described below.

In reference to FIG. 1, in one embodiment of the invention process 100,detrimental species-containing cellulosic biomass solids 2 is introducedinto first vessel 10A. An acidic solution 26A having a pH of at most 4,preferably at pH in the range of 0 to 3, at a temperature in the rangeof 0° C. to 60° C. is introduced into the first vessel 10A (“acid washstep”) as a first dispersed or semi-continuous liquid phase at a flux ofat least 1 kg/(m² s) in the presence of a first continuous gas phase,thereby producing an base washed cellulosic biomass solids. The acidcontent in the acidic solution is preferably less than 10 wt %, afterdilution of acid 4 by adding an aqueous solution that may be an aqueouseffluent from the process (such as 22A or 22B) to make stream 26A and/or26B as shown. The acid solution may optionally be placed in a reservoir26 and used as necessary for each treatment vessels. Then, an aqueoussolution 24A having a pH of at least 5 to at most 8 is introduced to theacid washed cellulosic biomass solids in the vessel 10A (“water rinsestep”) as a second dispersed or semi-continuous liquid phase at a fluxof at least 1 kg/(m² s) in the presence of a second continuous gasphase, optionally from an aqueous solution reservoir 24, therebyproducing water washed cellulosic biomass solids having at leastpartially reduced metal species content and anion content compared tothe detrimental species-containing cellulosic biomass solids and anacidic effluent 6A. Any rinse water from 10A that are no longer acidic(for example, having a pH of at least 5) may be acidified and used asthe acidic solution. The first dispersed or semi-continuous liquid phaseis recycled at least one time through the first vessel via conduit 25Ato effect multiple passes through the biomass being treated. The seconddispersed or semi-continuous liquid phase can also be recycled at leastone time through the first vessel via conduit 25A or another conduit(not shown) to effect multiple passes through the biomass being treated.The above steps is also repeated for the second vessel in a similarmanner to the first vessel. The detrimental species-containingcellulosic biomass solids 2 is introduced into the second vessel 10B. Anacidic solution 26B having a pH of at most 4, preferably at pH in therange of 0 to 3, at a temperature in the range of 0° C. to 60° C. isintroduced into the first vessel 10B (“acid wash step”) as a firstdispersed or semi-continuous liquid phase at a flux of at least 1 kg/(m²s) in the presence of a first continuous gas phase, thereby producing anbase washed cellulosic biomass solids. Then, an aqueous solution 24Bhaving a pH of at least 5 to at most 8 is introduced to the acid washedcellulosic biomass solids in the vessel 10B (“water rinse step”) as asecond dispersed or semi-continuous liquid phase at a flux of at least 1kg/(m² s) in the presence of a second continuous gas phase, optionallyfrom an aqueous solution reservoir 24, thereby producing water washedcellulosic biomass solids having at least partially reduced metalspecies content and anion content compared to the detrimentalspecies-containing cellulosic biomass solids and an acidic effluent 6B.Any rinse water from 10B that are no longer acidic (for example, havinga pH of at least 5) may be acidified and used as the acidic solution.

The first dispersed or semi-continuous liquid phase is recycled at leastone time through the first vessel via conduit 25B to effect multiplepasses through the biomass being treated. The second dispersed orsemi-continuous liquid phase can also be recycled at least one timethrough the first vessel via conduit 25B or another conduit (not shown)to effect multiple passes through the biomass being treated.

The same steps for the first vessel and second vessel may be carried outoptionally for the third vessel, fourth vessel, fifth vessel, sixthvessel, seventh vessel, eighth vessel, ninth vessel, tenth vessel, etc.up to n vessels.

The total acidic water effluent from the plurality of vessels maycomprise water initially present in the wet biomass feed and watergenerated in the process, with makeup water that is less than 50% of thebiomass feed (dry basis).

The above steps may be carried out in parallel in multiple vessels, eachvessels undergoing at least one of the steps, thus increasing theefficiency of the wash process.

At least a portion of the separated aqueous effluent is recycled via arecycle conduit to the second contact zone to form at least a portion ofthe aqueous solution 24. The pretreated cellulosic biomass is providedto digestion/reaction zone (“hydrothermal catalytic reaction zone orsystem”) 50 that may have one or more units, that in at least one unitcontaining a hydrothermal hydrocatalytic catalyst that is capable ofactivating molecular hydrogen to produce an intermediate oxygenatedproduct stream 56 containing oxygenated hydrocarbons and water in thepresence of hydrogen. Water may be removed from the oxygenatedhydrocarbon stream produced in the thermal catalytic zone and recycledvia 62 to form at least a portion of the aqueous solution 24. At least aportion of the oxygenated hydrocarbon stream may be converted in aconversion zone (not shown in Figures) to a hydrocarbon product streamcomprising hydrocarbons and water; and at least a portion of the watermay be separated and recycled 82 to the as the aqueous solution 24.Water may be separated from the hydrocarbon or from the oxygenatedhydrocarbon stream by conventional method including liquid/liquidseparation, decanting, distillation, or flashing.

If a base solution wash is desired after or before the acidic solutionwash, a base solution can be introduced to the respective treatmentvessels (first vessel, second vessel, etc. up to n vessels) optionallyfrom a reservoir of base solution and provided to each treatmentvessels. In one embodiment is shown in FIG. 2 If base treatment isdesired after the acidic solution wash, a base solution 28A having a pHof greater than 9, preferably having a pH of at most 13, more preferablyhaving a pH of at least 10, more preferably having a pH in the range of10 to 13, at a temperature in the range of 0° C. to 60° C. is introducedinto the first vessel 10A (“base wash step”) as a third dispersed orsemi-continuous liquid phase at a flux of at least 1 kg/(m² s) in thepresence of a third continuous gas phase, thereby producing an basewashed cellulosic biomass solids. The base content in the base solutionadjusted by dilution of base 5 by adding an aqueous solution that may bean aqueous effluent from the process (such as 29A or 29B) to make stream28A and/or 28B as shown. The base solution may optionally be placed in areservoir 28 and used as necessary for each treatment vessels. Then, anaqueous solution 24A having a pH of at least 5 to at most 8 isintroduced to the acid washed cellulosic biomass solids in the vessel10A (“second water rinse step”) as a fourth dispersed or semi-continuousliquid phase at a flux of at least 1 kg/(m² s) in the presence of afourth continuous gas phase, optionally from an aqueous solutionreservoir 24, thereby producing water washed cellulosic biomass solidshaving at least partially reduced metal species content and anioncontent compared to the detrimental species-containing cellulosicbiomass solids and a basic effluent 7A w. Any rinse water from 10A thatare no longer basic (for example, having a pH of at most 9) may be usedto provide the base solution.

The above steps is also repeated for the second vessel in a similarmanner to the first vessel. If base treatment is desired after theacidic solution wash, a base solution 28B having a pH of greater than 9,preferably having a pH of at most 13, more preferably having a pH of atleast 10, more preferably having a pH in the range of 10 to 13, at atemperature in the range of 0° C. to 60° C. is introduced into the firstvessel 10B (“base wash step”) as a third dispersed or semi-continuousliquid phase at a flux of at least 1 kg/(m² s) in the presence of athird continuous gas phase, thereby producing an base washed cellulosicbiomass solids. Then, an aqueous solution 24B having a pH of at least 5to at most 8 is introduced to the acid washed cellulosic biomass solidsin the vessel 10B (“second water rinse step”) as a fourth dispersed orsemi-continuous liquid phase at a flux of at least 1 kg/(m² s) in thepresence of a fourth continuous gas phase, optionally from an aqueoussolution reservoir 24, thereby producing water washed cellulosic biomasssolids having at least partially reduced metal species content and anioncontent compared to the detrimental species-containing cellulosicbiomass solids and a basic effluent 7B. Any rinse water from 10B thatare no longer basic (for example, having a pH of at most 9) may be usedto provide the base solution. The same steps for the first vessel andsecond vessel may be carried out optionally for the third vessel, fourthvessel, fifth vessel, sixth vessel, seventh vessel, eighth vessel, ninthvessel, tenth vessel, etc. up to n vessels.

The above steps may be carried out in parallel in multiple vessels, eachvessels undergoing at least one of the steps, thus increasing theefficiency of the wash process.

The total acidic water effluent and basic water effluent from theplurality of vessels may comprise water initially present in the wetbiomass feed and water generated in the process, with makeup water thatis less than 50% of the biomass feed (dry basis).

For the instant biofuels process, the minimization of fresh water usageis a key issue. However, due to biomass packing density being poor, atbest 3 parts or more of bed volume of water are required to typicallyfill a bed for washing one part of biomass. In the invention process,the detrimental species is removed with less than 5 parts, preferably atmost 2.5 parts, more preferably at most 2 parts, even at most 1.5 partsof water for washing one part of biomass. It is preferred that for theremoval process, only the water from the water in the biomass and watergenerated in the process

For the hydrothermal catalytic reaction zone, the zone may have one ormore vessels. In one embodiment in the digestion/reaction zonehydrolysis and hydrothermal hydrocatalytic reaction of the treatedbiomass is carried out in one or more vessels. These vessels may bedigesters or reactors or combination thereof including a combinationhydrothermal hydrocatalytic digestion unit.

In some embodiments, lignocellulosic biomass (solids) being added to thehydrothermal digestion unit or hydrothermal hydrocatalytic digestionunit may be pressurized before being added to the unit, particularlywhen the hydrothermal (hydrocatalytic) digestion unit is in apressurized state. Pressurization of the cellulosic biomass solids fromatmospheric pressure to a pressurized state may take place in one ormore pressurization zones before addition of the cellulosic biomasssolids to the hydrothermal (hydrocatalytic) digestion unit. Suitablepressurization zones that may be used for pressurizing and introducinglignocellulosic biomass to a pressurized hydrothermal digestion unit orhydrothermal hydrocatalytic digestion unit are described in more detailin commonly owned United States Patent Application PublicationsUS20130152457 and US20130152458, and incorporated herein by reference inits entirety. Suitable pressurization zones described therein mayinclude, for example, pressure vessels, pressurized screw feeders, andthe like. In some embodiments, multiple pressurization zones may beconnected in series to increase the pressure of the cellulosic biomasssolids in a stepwise manner. The digestion and the hydrothermalhydrocatalytic reaction in the hydrothermal catalytic reaction zone (ordigestion reaction zone) may be conducted separately, partiallycombined, or in situ.

In some embodiments, the digestion rate of cellulosic biomass solids maybe accelerated in the presence of a liquid phase containing a digestionsolvent. In some instances, the liquid phase may be maintained atelevated pressures that keep the digestion solvent in a liquid statewhen raised above its normal boiling point. Although the more rapiddigestion rate of cellulosic biomass solids under elevated temperatureand pressure conditions may be desirable from a throughput standpoint,soluble carbohydrates may be susceptible to degradation at elevatedtemperatures. One approach for addressing the degradation of solublecarbohydrates during hydrothermal digestion is to conduct an in situcatalytic reduction reaction process so as to convert the solublecarbohydrates into more stable compounds as soon as possible after theirformation.

In certain embodiments, a slurry catalyst may be effectively distributedfrom the bottom of a charge of cellulosic biomass solids to the topusing upwardly directed fluid flow to fluidize and upwardly conveyslurry catalyst particulates into the interstitial spaces within thecharge for adequate catalyst distribution within the digestingcellulosic biomass solids. Suitable techniques for using fluid flow todistribute a slurry catalyst within cellulosic biomass solids in such amanner are described in commonly owned United States Published PatentApplications US20140005445 and US20140005444, and incorporated herein byreference in its entirety. In addition to affecting distribution of theslurry catalyst, upwardly directed fluid flow may promote expansion ofthe cellulosic biomass solids and disfavor gravity-induced compactionthat occurs during their addition and digestion, particularly as thedigestion process proceeds and their structural integrity decreases.Methods of effectively distributing molecular hydrogen within cellulosicbiomass solids during hydrothermal digestion is further described incommonly owned United States Published Patent Applications US20140174433and US20140174432, each filed on filed on Dec. 20, 2012 and incorporatedherein by reference in its entirety.

In another embodiment the hydrothermal hydrocatalytic digestion unit maybe configured as disclosed in a co-pending United States PublishedPatent Application no. US20140117276, which disclosure is herebyincorporated by reference. In the digestion zone, the size-reducedbiomass is contacted with the digestive solvent where the digestionreaction takes place. The digestive solvent must be effective to digestlignins.

In some embodiments, at least a portion of oxygenated hydrocarbonsproduced in the hydrothermal hydrocatalytic reaction zone are recycledwithin the process and system to at least in part from the in situgenerated solvent, which is used in the biomass digestion process.Further, by controlling the degradation of carbohydrate in thehydrothermal hydrocatalytic reaction (e.g., hydrogenolysis process),hydrogenation reactions can be conducted along with the hydrogenolysisreaction at temperatures ranging from about 150° C. to 300° C. As aresult, a separate hydrogenation reaction section can optionally beavoided, and the fuel forming potential of the biomass feedstock fed tothe process can be increased. Further, it may be advantageous to use thein situ generated solvent as the organic solvent in the pretreatment.

In various embodiments, the fluid phase digestion medium in which thehydrothermal digestion and catalytic reduction reaction, in thehydrothermal hydrocatalytic reaction zone, are conducted may comprise anorganic solvent and water. Although any organic solvent that is at leastpartially miscible with water may be used as a digestion solvent,particularly advantageous organic solvents are those that can bedirectly converted into fuel blends and other materials without beingseparated from the alcoholic component being produced from thecellulosic biomass solids. That is, particularly advantageous organicsolvents are those that may be co-processed along with the alcoholiccomponent during downstream processing reactions into fuel blends andother materials. Suitable organic solvents in this regard may include,for example, ethanol, ethylene glycol, propylene glycol, glycerol,phenolics and any combination thereof. In situ generated organicsolvents are particularly desirable in this regard.

In some embodiments, the fluid phase digestion medium may comprisebetween about 1% water and about 99% water. Although higher percentagesof water may be more favorable from an environmental standpoint, higherquantities of organic solvent may more effectively promote hydrothermaldigestion due to the organic solvent's greater propensity to solubilizecarbohydrates and promote catalytic reduction of the solublecarbohydrates. In some embodiments, the fluid phase digestion medium maycomprise about 90% or less water by weight. In other embodiments, thefluid phase digestion medium may comprise about 80% or less water byweight, or about 70% or less water by weight, or about 60% or less waterby weight, or about 50% or less water by weight, or about 40% or lesswater by weight, or about 30% or less water by weight, or about 20% orless water by weight, or about 10% or less water by weight, or about 5%or less water by weight.

In some embodiments, hydrothermal hydrocatalytic catalysts, which arecapable of activating molecular hydrogen (e.g., hydrogenolysis catalyst)and conducting a catalytic reduction reaction may comprise a metal suchas, for example, Cr, Mo, W, Re, Mn, Cu, Cd, Fe, Co, Ni, Pt, Pd, Rh, Ru,Ir, Os, and alloys or any combination thereof, either alone or withpromoters such as Au, Ag, Cr, Zn, Mn, Sn, Bi, B, O, and alloys or anycombination thereof. In some embodiments, the catalysts and promotersmay allow for hydrogenation and hydrogenolysis reactions to occur at thesame time or in succession of one another. In some embodiments, suchcatalysts may also comprise a carbonaceous pyropolymer catalystcontaining transition metals (e.g., Cr, Mo, W, Re, Mn, Cu, and Cd) orGroup VIII metals (e.g., Fe, Co, Ni, Pt, Pd, Rh, Ru, Ir, and Os). Insome embodiments, the foregoing catalysts may be combined with analkaline earth metal oxide or adhered to a catalytically active support.In some or other embodiments, the catalyst may be deposited on acatalyst support that may not itself be catalytically active.

In some embodiments, the hydrothermal hydrocatalytic catalyst maycomprise a slurry catalyst. In some embodiments, the slurry catalyst maycomprise a poison-tolerant catalyst. As used herein the term“poison-tolerant catalyst” refers to a catalyst that is capable ofactivating molecular hydrogen without needing to be regenerated orreplaced due to low catalytic activity for at least about 12 hours ofcontinuous operation. Use of a poison-tolerant catalyst may beparticularly desirable when reacting soluble carbohydrates derived fromcellulosic biomass solids that have not had catalyst poisons removedtherefrom. Catalysts that are not poison tolerant may also be used toachieve a similar result, but they may need to be regenerated orreplaced more frequently than does a poison-tolerant catalyst.

In some embodiments, suitable poison-tolerant catalysts may include, forexample, sulfided catalysts. In some or other embodiments, nitridedcatalysts may be used as poison-tolerant catalysts. Sulfided catalystssuitable for activating molecular hydrogen and buffers suitable for usewith such catalysts are described in commonly owned United States PatentApplication Publications US20120317872, US20130109896, US20120317873,and US20140166221, each of which is incorporated herein by reference inits entirety. Sulfiding may take place by treating the catalyst withhydrogen sulfide or an alternative sulfiding agent, optionally while thecatalyst is disposed on a solid support. In more particular embodiments,the poison-tolerant catalyst may comprise (a) sulfur and (b) Mo or W and(c) Co and/or Ni or mixtures thereof. The pH buffering agent, may besuitable be an inorganic salt, particularly alkali salts such as, forexample, potassium hydroxide, sodium hydroxide, and potassium carbonateor ammonia. In other embodiments, catalysts containing Pt or Pd may alsobe effective poison-tolerant catalysts for use in the techniquesdescribed herein. When mediating in situ catalytic reduction reactionprocesses, sulfided catalysts may be particularly well suited to formreaction products comprising a substantial fraction of glycols (e.g.,C₂-C₆ glycols) without producing excessive amounts of the correspondingmonohydric alcohols. Although poison-tolerant catalysts, particularlysulfided catalysts, may be well suited for forming glycols from solublecarbohydrates, it is to be recognized that other types of catalysts,which may not necessarily be poison-tolerant, may also be used toachieve a like result in alternative embodiments. As will be recognizedby one having ordinary skill in the art, various reaction parameters(e.g., temperature, pressure, catalyst composition, introduction ofother components, and the like) may be modified to favor the formationof a desired reaction product. Given the benefit of the presentdisclosure, one having ordinary skill in the art will be able to altervarious reaction parameters to change the product distribution obtainedfrom a particular catalyst and set of reactants.

In some embodiments, slurry catalysts suitable for use in the methodsdescribed herein may be sulfided by dispersing a slurry catalyst in afluid phase and adding a sulfiding agent thereto. Suitable sulfidingagents may include, for example, organic sulfoxides (e.g., dimethylsulfoxide), hydrogen sulfide, salts of hydrogen sulfide (e.g., NaSH),and the like. In some embodiments, the slurry catalyst may beconcentrated in the fluid phase after sulfiding, and the concentratedslurry may then be distributed in the cellulosic biomass solids usingfluid flow. Illustrative techniques for catalyst sulfiding that may beused in conjunction with the methods described herein are described inUnited States Patent Application Publication US20100236988 andincorporated herein by reference in its entirety.

In various embodiments, slurry catalysts used in conjunction with themethods described herein may have a particulate size of about 250microns or less. In some embodiments, the slurry catalyst may have aparticulate size of about 100 microns or less, or about 10 microns orless. In some embodiments, the minimum particulate size of the slurrycatalyst may be about 1 micron. In some embodiments, the slurry catalystmay comprise catalyst fines in the processes described herein.

Catalysts that are not particularly poison-tolerant may also be used inconjunction with the techniques described herein. Such catalysts mayinclude, for example, Ru, Pt, Pd, or compounds thereof disposed on asolid support such as, for example, Ru on titanium dioxide or Ru oncarbon. Although such catalysts may not have particular poisontolerance, they may be regenerable, such as through exposure of thecatalyst to water at elevated temperatures, which may be in either asubcritical state or a supercritical state.

In some embodiments, the catalysts used in conjunction with theprocesses described herein may be operable to generate molecularhydrogen. For example, in some embodiments, catalysts suitable foraqueous phase reforming (i.e., APR catalysts) may be used. Suitable APRcatalysts may include, for example, catalysts comprising Pt, Pd, Ru, Ni,Co, or other Group VIII metals alloyed or modified with Re, Mo, Sn, orother metals such as described in United States Patent PublicationUS20080300435 and incorporated herein by reference in its entirety.

In some embodiments, the alcoholic component formed from the cellulosicbiomass solids may be further reformed into a biofuel. Reforming thealcoholic component into a biofuel or other material may comprise anycombination and sequence of further hydrogenolysis reactions and/orhydrogenation reactions, condensation reactions, isomerizationreactions, oligomerization reactions, hydrotreating reactions,alkylation reactions, dehydration reactions, desulfurization reactions,and the like. The subsequent conversion reactions may be catalytic ornon-catalytic. In some embodiments, an initial operation of downstreamconversion may comprise a condensation reaction, often conducted in thepresence of a condensation catalyst, in which the alcoholic component ora product derived therefrom is condensed with another molecule to form ahigher molecular weight compound. As used herein, the term “condensationreaction” will refer to a chemical transformation in which two or moremolecules are coupled with one another to form a carbon-carbon bond in ahigher molecular weight compound, usually accompanied by the loss of asmall molecule such as water or an alcohol. An illustrative condensationreaction is the Aldol condensation reaction, which will be familiar toone having ordinary skill in the art. Additional disclosure regardingcondensation reactions and catalysts suitable for promoting condensationreactions is provided hereinbelow.

In some embodiments, methods described herein may further compriseperforming a condensation reaction on the alcoholic component or aproduct derived therefrom. In various embodiments, the condensationreaction may take place at a temperature ranging between about 5° C. andabout 500° C. The condensation reaction may take place in a condensedphase (e.g., a liquor phase) or in a vapor phase. For condensationreactions taking place in a vapor phase, the temperature may rangebetween about 75° C. and about 500° C., or between about 125° C. andabout 450° C. For condensation reactions taking place in a condensedphase, the temperature may range between about 5° C. and about 475° C.,or between about 15° C. and about 300° C., or between about 20° C. andabout 250° C.

Each reactor vessel preferably includes an inlet and an outlet adaptedto remove the product stream from the vessel or reactor. In someembodiments, the vessel in which at least some digestion occurs mayinclude additional outlets to allow for the removal of portions of thereactant stream. In some embodiments, the vessel in which at least somedigestion occurs may include additional inlets to allow for additionalsolvents or additives.

In various embodiments, the higher molecular weight compound produced bythe condensation reaction may comprise ≧C₄ hydrocarbons. In some orother embodiments, the higher molecular weight compound produced by thecondensation reaction may comprise ≧C₆ hydrocarbons. In someembodiments, the higher molecular weight compound produced by thecondensation reaction may comprise C₄-C₃₀ hydrocarbons. In someembodiments, the higher molecular weight compound produced by thecondensation reaction may comprise C₆-C₃₀ hydrocarbons. In still otherembodiments, the higher molecular weight compound produced by thecondensation reaction may comprise C₄-C₂₄ hydrocarbons, or C₆-C₂₄hydrocarbons, or C₄-C₁₈ hydrocarbons, or C₆-C₁₈ hydrocarbons, or C₄-C₁₂hydrocarbons, or C₆-C₁₂ hydrocarbons. As used herein, the term“hydrocarbons” refers to compounds containing both carbon and hydrogenwithout reference to other elements that may be present. Thus,heteroatom-substituted compounds are also described herein by the term“hydrocarbons.”

The particular composition of the higher molecular weight compoundproduced by the condensation reaction may vary depending on thecatalyst(s) and temperatures used for both the catalytic reductionreaction and the condensation reaction, as well as other parameters suchas pressure.

In some embodiments, a single catalyst may mediate the transformation ofthe alcoholic component into a form suitable for undergoing acondensation reaction as well as mediating the condensation reactionitself. In other embodiments, a first catalyst may be used to mediatethe transformation of the alcoholic component into a form suitable forundergoing a condensation reaction, and a second catalyst may be used tomediate the condensation reaction. Unless otherwise specified, it is tobe understood that reference herein to a condensation reaction andcondensation catalyst refers to either type of condensation process.Further disclosure of suitable condensation catalysts now follows.

In some embodiments, a single catalyst may be used to form a highermolecular weight compound via a condensation reaction. Without beingbound by any theory or mechanism, it is believed that such catalysts maymediate an initial dehydrogenation of the alcoholic component, followedby a condensation reaction of the dehydrogenated alcoholic component.Zeolite catalysts are one type of catalyst suitable for directlyconverting alcohols to condensation products in such a manner. Aparticularly suitable zeolite catalyst in this regard may be ZSM-5,although other zeolite catalysts may also be suitable.

In some embodiments, two catalysts may be used to form a highermolecular weight compound via a condensation reaction. Without beingbound by any theory or mechanism, it is believed that the first catalystmay mediate an initial dehydrogenation of the alcoholic component, andthe second catalyst may mediate a condensation reaction of thedehydrogenated alcoholic component. Like the single-catalyst embodimentsdiscussed previously above, in some embodiments, zeolite catalysts maybe used as either the first catalyst or the second catalyst. Again, aparticularly suitable zeolite catalyst in this regard may be ZSM-5,although other zeolite catalysts may also be suitable.

Various catalytic processes may be used to form higher molecular weightcompounds by a condensation reaction. In some embodiments, the catalystused for mediating a condensation reaction may comprise a basic site, orboth an acidic site and a basic site. Catalysts comprising both anacidic site and a basic site will be referred to herein asmulti-functional catalysts. In some or other embodiments, a catalystused for mediating a condensation reaction may comprise one or moremetal atoms. Any of the condensation catalysts may also optionally bedisposed on a solid support, if desired.

In some embodiments, the condensation catalyst may comprise a basiccatalyst comprising Li, Na, K, Cs, B, Rb, Mg, Ca, Sr, Si, Ba, Al, Zn,Ce, La, Y, Sc, Y, Zr, Ti, hydrotalcite, zinc-aluminate, phosphate,base-treated aluminosilicate zeolite, a basic resin, basic nitride,alloys or any combination thereof. In some embodiments, the basiccatalyst may also comprise an oxide of Ti, Zr, V, Nb, Ta, Mo, Cr, W, Mn,Re, Al, Ga, In, Co, Ni, Si, Cu, Zn, Sn, Cd, Mg, P, Fe, or anycombination thereof. In some embodiments, the basic catalyst maycomprise a mixed-oxide basic catalyst. Suitable mixed-oxide basiccatalysts may comprise, for example, Si—Mg—O, Mg—Ti—O, Y—Mg—O, Y—Zr—O,Ti—Zr—O, Ce—Zr—O, Ce—Mg—O, Ca—Zr—O, La—Zr—O, B—Zr—O, La—Ti—O, B—Ti—O,and any combination thereof. In some embodiments, the condensationcatalyst may further include a metal or alloys comprising metals suchas, for example, Cu, Ag, Au, Pt, Ni, Fe, Co, Ru, Zn, Cd, Ga, In, Rh, Pd,Ir, Re, Mn, Cr, Mo, W, Sn, Bi, Pb, Os, alloys and combinations thereof.Use of metals in the condensation catalyst may be desirable when adehydrogenation reaction is to be carried out in concert with thecondensation reaction. Basic resins may include resins that exhibitbasic functionality. The basic catalyst may be self-supporting oradhered to a support containing a material such as, for example, carbon,silica, alumina, zirconia, titania, vanadia, ceria, nitride, boronnitride, a heteropolyacid, alloys and mixtures thereof.

In some embodiments, the condensation catalyst may comprise ahydrotalcite material derived from a combination of MgO and Al₂O₃. Insome embodiments, the condensation catalyst may comprise a zincaluminate spinel formed from a combination of ZnO and Al₂O₃. In stillother embodiments, the condensation catalyst may comprise a combinationof ZnO, Al₂O₃, and CuO. Each of these materials may also contain anadditional metal or alloy, including those more generally referencedabove for basic condensation catalysts. In more particular embodiments,the additional metal or alloy may comprise a Group 10 metal such Pd, Pt,or any combination thereof.

In some embodiments, the condensation catalyst may comprise a basiccatalyst comprising a metal oxide containing, for example, Cu, Ni, Zn,V, Zr, or any mixture thereof. In some or other embodiments, thecondensation catalyst may comprise a zinc aluminate containing, forexample, Pt, Pd, Cu, Ni, or any mixture thereof.

In some embodiments, the condensation catalyst may comprise amulti-functional catalyst having both an acidic functionality and abasic functionality. Such condensation catalysts may comprise ahydrotalcite, a zinc-aluminate, a phosphate, Li, Na, K, Cs, B, Rb, Mg,Si, Ca, Sr, Ba, Al, Ce, La, Sc, Y, Zr, Ti, Zn, Cr, or any combinationthereof. In further embodiments, the multi-functional catalyst may alsoinclude one or more oxides from the group of Ti, Zr, V, Nb, Ta, Mo, Cr,W, Mn, Re, Al, Ga, In, Fe, Co, Ir, Ni, Si, Cu, Zn, Sn, Cd, P, and anycombination thereof. In some embodiments, the multi-functional catalystmay include a metal such as, for example, Cu, Ag, Au, Pt, Ni, Fe, Co,Ru, Zn, Cd, Ga, In, Rh, Pd, Ir, Re, Mn, Cr, Mo, W, Sn, Os, alloys orcombinations thereof. The basic catalyst may be self-supporting oradhered to a support containing a material such as, for example, carbon,silica, alumina, zirconia, titania, vanadia, ceria, nitride, boronnitride, a heteropolyacid, alloys and mixtures thereof.

In some embodiments, the condensation catalyst may comprise a metaloxide containing Pd, Pt, Cu or Ni. In still other embodiments, thecondensation catalyst may comprise an aluminate or a zirconium metaloxide containing Mg and Cu, Pt, Pd or Ni. In still other embodiments, amulti-functional catalyst may comprise a hydroxyapatite (HAP) combinedwith one or more of the above metals.

In some embodiments, the condensation catalyst may also include azeolite and other microporous supports that contain Group IA compounds,such as Li, Na, K, Cs and Rb. Preferably, the Group IA material may bepresent in an amount less than that required to neutralize the acidicnature of the support. A metal function may also be provided by theaddition of group VIIIB metals, or Cu, Ga, In, Zn or Sn. In someembodiments, the condensation catalyst may be derived from thecombination of MgO and Al₂O₃ to form a hydrotalcite material. Anothercondensation catalyst may comprise a combination of MgO and ZrO₂, or acombination of ZnO and Al₂O₃. Each of these materials may also containan additional metal function provided by copper or a Group VIIIB metal,such as Ni, Pd, Pt, or combinations of the foregoing.

The condensation reaction mediated by the condensation catalyst may becarried out in any reactor of suitable design, includingcontinuous-flow, batch, semi-batch or multi-system reactors, withoutlimitation as to design, size, geometry, flow rates, and the like. Thereactor system may also use a fluidized catalytic bed system, a swingbed system, fixed bed system, a moving bed system, or a combination ofthe above. In some embodiments, bi-phasic (e.g., liquid-liquid) andtri-phasic (e.g., liquid-liquid-solid) reactors may be used to carry outthe condensation reaction.

In some embodiments, an acid catalyst may be used to optionallydehydrate at least a portion of the reaction product. Suitable acidcatalysts for use in the dehydration reaction may include, but are notlimited to, mineral acids (e.g., HCl, H₂SO₄), solid acids (e.g.,zeolites, ion-exchange resins) and acid salts (e.g., LaCl₃). Additionalacid catalysts may include, without limitation, zeolites, carbides,nitrides, zirconia, alumina, silica, aluminosilicates, phosphates,titanium oxides, zinc oxides, vanadium oxides, lanthanum oxides, yttriumoxides, scandium oxides, magnesium oxides, cerium oxides, barium oxides,calcium oxides, hydroxides, heteropolyacids, inorganic acids, acidmodified resins, base modified resins, and any combination thereof. Insome embodiments, the dehydration catalyst may also include a modifier.Suitable modifiers may include, for example, La, Y, Sc, P, B, Bi, Li,Na, K, Rb, Cs, Mg, Ca, Sr, Ba, and any combination thereof. Themodifiers may be useful, inter alia, to carry out a concertedhydrogenation/dehydrogenation reaction with the dehydration reaction. Insome embodiments, the dehydration catalyst may also include a metal.Suitable metals may include, for example, Cu, Ag, Au, Pt, Ni, Fe, Co,Ru, Zn, Cd, Ga, In, Rh, Pd, Ir, Re, Mn, Cr, Mo, W, Sn, Os, alloys, andany combination thereof. The dehydration catalyst may beself-supporting, supported on an inert support or resin, or it may bedissolved in a fluid.

Various operations may optionally be performed on the alcoholiccomponent prior to conducting a condensation reaction. In addition,various operations may optionally be performed on a fluid phasecontaining the alcoholic component, thereby further transforming thealcoholic component or placing the alcoholic component in a form moresuitable for taking part in a condensation reaction. These optionaloperations are now described in more detail below.

As described above, one or more liquid phases may be present whendigesting cellulosic biomass solids. Particularly when cellulosicbiomass solids are fed continuously or semi-continuously to thehydrothermal (hydrocatalytic) digestion unit, digestion of thecellulosic biomass solids may produce multiple liquid phases in thehydrothermal digestion unit. The liquid phases may be immiscible withone another, or they may be at least partially miscible with oneanother. In some embodiments, the one or more liquid phases may comprisea phenolics liquid phase comprising lignin or a product formedtherefrom, an aqueous phase comprising the alcoholic component, a lightorganics phase, or any combination thereof. The alcoholic componentbeing produced from the cellulosic biomass solids may be partitionedbetween the one or more liquid phases, or the alcoholic component may belocated substantially in a single liquid phase. For example, thealcoholic component being produced from the cellulosic biomass solidsmay be located predominantly in an aqueous phase (e.g., an aqueous phasedigestion solvent), although minor amounts of the alcoholic componentmay be partitioned to the phenolics liquid phase or a light organicsphase. In various embodiments, the slurry catalyst may accumulate in thephenolics liquid phase as it forms, thereby complicating the return ofthe slurry catalyst to the cellulosic biomass solids in the mannerdescribed above. Alternative configurations for distributing slurrycatalyst particulates in the cellulosic biomass solids when excessivecatalyst accumulation in the phenolics liquid phase has occurred aredescribed hereinafter.

Accumulation of the slurry catalyst in the phenolics liquid phase may,in some embodiments, be addressed by conveying this phase and theaccumulated slurry catalyst therein to the same location where a fluidphase digestion medium is being contacted with cellulosic biomasssolids. The fluid phase digestion medium and the phenolics liquid phasemay be conveyed to the cellulosic biomass solids together or separately.Thusly, either the fluid phase digestion medium and/or the phenolicsliquid phase may motively return the slurry catalyst back to thecellulosic biomass solids such that continued stabilization of solublecarbohydrates may take place. In some embodiments, at least a portion ofthe lignin in the phenolics liquid phase may be depolymerized before orwhile conveying the phenolics liquid phase for redistribution of theslurry catalyst. At least partial depolymerization of the lignin in thephenolics liquid phase may reduce the viscosity of this phase and makeit easier to convey. Lignin depolymerization may take place chemicallyby hydrolyzing the lignin (e.g., with a base) or thermally by heatingthe lignin to a temperature of at least about 250° C. in the presence ofmolecular hydrogen and the slurry catalyst. Further details regardinglignin depolymerization and the use of viscosity monitoring as a meansof process control are described in commonly owned United StatesPublished Patent Application US20140117275, incorporated herein byreference in its entirety.

After forming the alcoholic component from the cellulosic biomasssolids, at least a portion of the alcoholic component may be separatedfrom the cellulosic biomass solids and further processed by performing acondensation reaction thereon, as generally described above. Processingof the alcoholic component that has partitioned between various liquidphases may take place with the phases separated from one another, orwith the liquid phases mixed together. For example, in some embodiments,the alcoholic component in a fluid phase digestion medium may beprocessed separately from a light organics phase. In other embodiments,the light organics phase may be processed concurrently with the fluidphase digestion medium.

Optionally, the fluid phase digestion medium containing the alcoholiccomponent may be subjected to a second catalytic reduction reactionexternal to the cellulosic biomass solids, if needed, for example, toincrease the amount of soluble carbohydrates that are converted into thealcoholic component and/or to further reduce the degree of oxygenationof the alcoholic components that are formed. For example, in someembodiments, a glycol or more highly oxygenated alcohol may betransformed into a monohydric alcohol by performing a second catalyticreduction reaction. The choice of whether to perform a condensationreaction on a monohydric alcohol or a glycol may be based on a number offactors, as discussed in more detail below, and each approach maypresent particular advantages.

In some embodiments, a glycol produced from the cellulosic biomasssolids may be fed to the condensation catalyst. Although glycols may beprone to coking when used in conjunction with condensation catalysts,particularly zeolite catalysts, the present inventors found the degreeof coking to be manageable in the production of higher molecular weightcompounds. Approaches for producing glycols from cellulosic biomasssolids and feeding the glycols to a condensation catalyst are describedin commonly owned United States Patent Application US20140121420,incorporated herein by reference in its entirety.

In some embodiments, a phenolics liquid phase formed from the cellulosicbiomass solids may be further processed. Processing of the phenolicsliquid phase may facilitate the catalytic reduction reaction beingperformed to stabilize soluble carbohydrates. In addition, furtherprocessing of the phenolics liquid phase may be coupled with theproduction of dried glycols or dried monohydric alcohols for feeding toa condensation catalyst. Moreover, further processing of the phenolicsliquid phase may produce methanol and phenolic compounds fromdegradation of the lignin present in the cellulosic biomass solids,thereby increasing the overall weight percentage of the cellulosicbiomass solids that may be transformed into useful materials. Finally,further processing of the phenolics liquid phase may improve thelifetime of the slurry catalyst.

These liquid phases or fluid phases can be used to remove water in thepretreatment as organic solvent, in the third contact zone, and thus beavailable for further processing

Various techniques for processing a phenolics liquid phase produced fromcellulosic biomass solids are described in commonly owned United StatesPublished Patent Applications US20140121419, US20140117277, andUS20140121418, incorporated herein by reference in its entirety. Asdescribed therein, in some embodiments, the viscosity of the phenolicsliquid phase may be reduced in order to facilitate conveyance orhandling of the phenolics liquid phase. As further described therein,deviscosification of the phenolics liquid phase may take place bychemically hydrolyzing the lignin and/or heating the phenolics liquidphase in the presence of molecular hydrogen (i.e., hydrotreating) todepolymerize at least a portion of the lignin present therein in thepresence of accumulated slurry catalyst. Deviscosification of thephenolics liquid phase may take place before or after separation of thephenolics liquid phase from one or more of the other liquid phasespresent, and thermal deviscosification may be coupled to the reaction orseries of reactions used to produce the alcoholic component from thecellulosic biomass solids. Moreover, after deviscosification of thephenolics liquid phase, the slurry catalyst may be removed therefrom.The catalyst may then be regenerated, returned to the cellulosic biomasssolids, or any combination thereof.

In some embodiments, heating of the cellulosic biomass solids and thefluid phase digestion medium to form soluble carbohydrates and aphenolics liquid phase may take place while the cellulosic biomasssolids are in a pressurized state. As used herein, the term “pressurizedstate” refers to a pressure that is greater than atmospheric pressure (1bar). Heating a fluid phase digestion medium in a pressurized state mayallow the normal boiling point of the digestion solvent to be exceeded,thereby allowing the rate of hydrothermal digestion to be increasedrelative to lower temperature digestion processes. In some embodiments,heating the cellulosic biomass solids and the fluid phase digestionmedium may take place at a pressure of at least about 30 bar. In someembodiments, heating the cellulosic biomass solids and the fluid phasedigestion medium may take place at a pressure of at least about 60 bar,or at a pressure of at least about 90 bar. In some embodiments, heatingthe cellulosic biomass solids and the fluid phase digestion medium maytake place at a pressure ranging between about 30 bar and about 430 bar.In some embodiments, heating the cellulosic biomass solids and the fluidphase digestion medium may take place at a pressure ranging betweenabout 50 bar and about 330 bar, or at a pressure ranging between about70 bar and about 130 bar, or at a pressure ranging between about 30 barand about 130 bar.

To facilitate a better understanding of the present invention, thefollowing examples of preferred embodiments are given. In no way shouldthe following examples be read to limit, or to define, the scope of theinvention.

ILLUSTRATIVE EXAMPLES Example 1 Trickle Bed Acid Wash

A 25-mm inside diameter by 350-mm glass chromatography column was packedwith 44.5 grams of southern pine (39.5% moisture), filling 180milliliters of bed volume. An acidic treatment solution of 1 wt %sulfuric acid in deionized water was prepared. Acid wash was poured intothe top of the bed in slugs of 17.4, 14.7, 14.8, and 15.2 grams, thetotal of which comprised 34% of the volume of the bed. 33 grams oftreatment effluent were collected, and recycled ten times by pouringback into the top of the bed to effect another contacting cycle, and8-15 minute intervals. 24.9 grams were collected after ten recycles.

The effluent acid treatment was analyzed for metals via plasma emissionspectroscopy. Results (Table 1) show removal of calcium, potassium,magnesium, as well as transition metals manganese and iron via the acidwash trickle bed treatment. Silicon from silica impurity was alsoremoved by the wash procedure, among other metals removed.

Manganese removal corresponded to an estimated 46% of that present inthe initial wood sample, using an acidic effluent treatment that wasonly 15% of the bed volume of the biomass charged. This example showsthe efficiency of trickle bed contacting, in removal of impurities usinga water volume that is only a fraction of the volume of the biomass bed.

TABLE 1 Metals Removal by Acid Wash in Trickle bed mode ppm wt in acidELEMENT/RESULT effluent Nickel 0.3 Cadmium <1 Zinc 2 Silicon 6.0 Boron 2Phosphorous 4 Manganese 28 Magnesium 94 Molybdenum <0.1 Vanadium <0.1Titanium 0.1 Copper 1 Cobalt 0.1 Aluminum 3 Lead <1 Iron 1 Potassium 145Sodium 41 Chromium 0.1 Calcium 278

Example 2 Trickle Bed Base Wash

A 25-mm inside diameter by 350-mm glass chromatography column was packedwith 30.1 grams of southern pine (39.5% moisture) to a height of 240 mm,filling 118 milliliters of bed volume. 40 grams of 1N KOH were pouredinto the bed at the top, and allowed to drain for 30 minute. Theeffluent was collected and recycled 10 times, producing 9.98 grams ofeffluent that were analyzed by ion chromatography for chlorides andphosphates. The base wash effluent was found to contain 20.4 ppmchloride and 25.1 ppm phosphate, removed by the trickle bed treatmentprocess.

The chloride concentration was 33% higher than the maximum observed intreatments using a larger amount of base, for a wood bed fully immersedin aqueous base solution. Despite producing a final wash that was only8% of a bed volume, nearly 16% of the chlorine present on the wood wasremoved via recycle contacting. Additional chloride and phosphateremoval is expected for additional base washing cycles using fresh basetreatment.

This example shows the high efficiency in use of trickle bed contacting,where a small volume of aqueous treatment can remove substantialconcentrations of impurities from biomass, thus minimizing the waterrequired for pretreatment.

What is claims is:
 1. A method for selective removal of detrimentalmetals and their anion species from a cellulosic biomass solids, saidmethod comprising a plurality of vessels: a. providing each of saidvessels with one of detrimental species-containing cellulosic biomasssolids; b. introducing a first dispersed or semi-continuous liquid phasecomprising an acidic solution having a pH of at most 4 from an inletinto a first vessel of said plurality of vessel wherein the cellulosicbiomass solids in the first vessel is contacted by said first dispersedor semi-continuous liquid phase and first continuous gas phase at atemperature in the range of about 0° C. to about 60° C. wherein the fluxof the first liquid phase is at least 1 kg/(m² s); c. repeating step (b)for a second vessel of said plurality of vessels; d. introducing asecond dispersed or semi-continuous liquid phase comprising an aqueoussolution having a pH of at least 5 from an inlet into said first vesselof said plurality of vessels treated according to step (b) wherein saidacidic solution-treated cellulosic biomass solids in the first vessel iscontacted by said second dispersed or semi-continuous liquid phase andsecond continuous gas phase wherein the flux of the second liquid phaseis at least 1 kg/(m² s) and discharging an acidic effluent; e. repeatingstep (d) for the second vessel of said plurality of vessels treatedaccording to step (c); f. introducing a third dispersed orsemi-continuous liquid phase comprising a base solution having a pH ofgreater than 9 from an inlet into said first vessel of said plurality ofvessels treated according to step (d) wherein said aqueoussolution-treated cellulosic biomass solids in the first vessel iscontacted by said third dispersed or semi-continuous liquid phase andthird continuous gas phase wherein the flux of the third liquid phase isat least 1 kg/(m² s) and discharging an aqueous effluent; g. repeatingstep (f) for a second vessel of said plurality of vessels treatedaccording to step (e); h. introducing a fourth dispersed orsemi-continuous liquid phase comprising an aqueous solution having a pHof at most 8 from an inlet into said first vessel of said plurality ofvessels treated according to step (f) wherein said base solution-treatedcellulosic biomass solids in the first vessel is contacted by saidfourth dispersed or semi-continuous liquid phase and fourth continuousgas phase wherein the flux of the fourth liquid phase is at least 1kg/(m² s) and discharging a basic effluent; i. repeating step (h) forthe second vessel of said plurality of vessels treated according to step(g); j. transferring at least a portion of the biomass treated accordingto steps (h) and (i) to a digestion and/or reaction vessel; k. whereinat least 2 of the vessels are undergoing at least one of the steps (b)through (j) at the same time; and l. wherein the amount of the totaldischarged acidic effluent and basic effluent from the plurality ofvessels is in the range of from about 3 parts to about 0.5 partsrelative to about 1 part of detrimental species-containing cellulosicbiomass solids (dry basis).
 2. The method of claim 1 wherein steps (b),(d), (f), (h), or (j) are repeated for n vessels where n is an integerfrom 2 to
 20. 3. The method of claim 2 wherein n is an integer from 2 to10.
 4. The method of claim 3 wherein n is an integer from 3 to
 6. 5. Themethod of claim 1 wherein the first dispersed or semi-continuous liquidphase, is recycled at least one time through the first vessel for step(b) and through the second vessel for step (c).
 6. The method of claim 1wherein the second dispersed or semi-continuous liquid phase, isrecycled at least one time through the first vessel for step (d) andthrough the second vessel for step (e).
 7. The method of claim 1 whereinthe acidic effluent is discharged until the pH is greater than 3 oruntil the amount of the acidic effluent exceeds the acidic solutionintroduced into the vessel, and at least a portion of the subsequentaqueous effluent is recycled at least one time through the first vessel.8. The method of claim 7 wherein at least a portion of the subsequentaqueous effluent is recycled as the acidic solution.
 9. The method ofclaim 8 further adjusting the pH of at least a portion of the subsequentaqueous effluent to a pH of at most 4 by adding an acid to thedischarged aqueous solution prior to recycling as a portion of theacidic solution.
 10. The method of claim 1 wherein the third dispersedor semi-continuous liquid phase, is recycled at least one time throughthe first vessel for step (f) and through the second vessel for step(g).
 11. The method of claim 1 wherein the fourth dispersed orsemi-continuous liquid phase, is recycled at least one time through thefirst vessel for step (h) and through the second vessel for step (i).12. The method of claim 1 wherein the basic effluent is discharged untilthe pH is less than 9 or until the amount of the basic effluent exceedsthe base solution introduced into the vessel, and at least a portion ofthe subsequent aqueous effluent is recycled at least one time throughthe first vessel.
 13. The method of claim 12 wherein at least a portionof the subsequent aqueous effluent is recycled as the base solution. 14.The method of claim 13 further adjusting the pH of at least a portion ofthe subsequent aqueous effluent to a pH of greater than 9 by adding abase to the discharged aqueous solution prior to recycling as a portionof the base solution.
 15. The method of claim 1 wherein, in thedigestion and/or reaction zone, the treated cellulosic biomass iscontacted with a hydrothermal hydrocatalytic catalyst in the presence ofhydrogen and a digestion solvent thereby producing an intermediateoxygenated product stream comprising oxygenated hydrocarbons and water;and at least a portion of the water is separated and recycled as theaqueous solution.
 16. The method of claim 1 wherein, in the digestionand/or reaction zone, the treated cellulosic biomass is contacted with ahydrothermal hydrocatalytic catalyst in the presence of hydrogen and adigestion solvent thereby producing an intermediate oxygenated productstream; at least a portion of the oxygenated intermediate product streamis converted to a hydrocarbon product stream comprising hydrocarbons andwater; and at least a portion of the water is separated and recycled asthe aqueous solution.
 17. The method of claim 15 wherein, the oxygenatedintermediate product stream comprises oxygenated hydrocarbons and water,and at least a portion of the water is separated and recycled as theaqueous solution.
 18. A method for selective removal of detrimentalmetals and their anion species from a cellulosic biomass solids, saidmethod comprising a plurality of vessels: a. providing each of saidvessels with one of detrimental species-containing cellulosic biomasssolids; b. introducing a first dispersed or semi-continuous liquid phasecomprising a base solution having a pH of greater than 9 from an inletinto a first vessel of said plurality of vessel wherein the cellulosicbiomass solids in the first vessel is contacted by said first dispersedor semi-continuous liquid phase and first continuous gas phase at atemperature in the range of about 0° C. to about 60° C. wherein the fluxof the first liquid phase is at least 1 kg/(m² s); c. repeating step (b)for a second vessel of said plurality of vessels; d. introducing asecond dispersed or semi-continuous liquid phase comprising an aqueoussolution having a pH of at most 8 from an inlet into said first vesselof said plurality of vessels treated according to step (b) wherein saidbase solution-treated cellulosic biomass solids in the first vessel iscontacted by said second dispersed or semi-continuous liquid phase andsecond continuous gas phase wherein the flux of the second liquid phaseis at least 1 kg/(m² s) and discharging a basic effluent; e. repeatingstep (d) for the second vessel of said plurality of vessels treatedaccording to step (c); f. introducing a third t dispersed orsemi-continuous liquid phase comprising an acidic solution having a pHof at most 4 from an inlet into a first vessel of said plurality ofvessel treated according to step (d) wherein the cellulosic biomasssolids in the first vessel is contacted by said third dispersed orsemi-continuous liquid phase and third continuous gas phase at atemperature in the range of about 0° C. to about 60° C. wherein the fluxof the first liquid phase is at least 1 kg/(m² s); g. repeating step (f)for a second vessel of said plurality of vessels treated according tostep (e); h. introducing a fourth dispersed or semi-continuous liquidphase comprising an aqueous solution having a pH of at least 5 from aninlet into said first vessel of said plurality of vessels treatedaccording to step (f) wherein said acidic solution-treated cellulosicbiomass solids in the first vessel is contacted by said fourth dispersedor semi-continuous liquid phase and fourth continuous gas phase whereinthe flux of the fourth liquid phase is at least 1 kg/(m² s) anddischarging an acidic effluent; i. repeating step (h) for the secondvessel of said plurality of vessels treated according to step (g); j.transferring at least a portion of the biomass treated according tosteps (h) and (i) to a digestion and/or reaction vessel; k. wherein atleast 2 of the vessels are undergoing at least one of the steps (b)through (j) at the same time; and l. wherein the amount of the totaldischarged acidic solution and base solution from the plurality ofvessels is in the range of from about 3 parts to about 0.5 partsrelative to about 1 part of detrimental species-containing cellulosicbiomass solids (dry basis).
 19. The method of claim 18 wherein steps(b), (d), (f), (h), or (j) are repeated for n vessels where n is aninteger from 2 to
 20. 20. The method of claim 19 wherein n is an integerfrom 2 to
 10. 21. The method of claim 20 wherein n is an integer from 3to
 6. 22. The method of claim 18 wherein the first dispersed orsemi-continuous liquid phase, is recycled at least one time through thefirst vessel for step (b) and through the second vessel for step (c).23. The method of claim 18 wherein the second dispersed orsemi-continuous liquid phase, is recycled at least one time through thefirst vessel for step (d) and through the second vessel for step (e).24. The method of claim 18 wherein the acidic effluent is dischargeduntil the pH is greater than 3 or until the amount of the acidiceffluent exceeds the acidic solution introduced into the vessel, and atleast a portion of the subsequent aqueous effluent is recycled at leastone time through the first vessel.
 25. The method of claim 24 wherein atleast a portion of the subsequent aqueous effluent is recycled as theacidic solution.
 26. The method of claim 25 further adjusting the pH ofat least a portion of the subsequent aqueous effluent to a pH of at most4 by adding an acid to the discharged aqueous solution prior torecycling as a portion of the acidic solution.
 27. The method of claim18 wherein the third dispersed or semi-continuous liquid phase, isrecycled at least one time through the first vessel for step (f) andthrough the second vessel for step (g).
 28. The method of claim 18wherein the fourth dispersed or semi-continuous liquid phase, isrecycled at least one time through the first vessel for step (h) andthrough the second vessel for step (i).
 29. The method of claim 18wherein the basic effluent is discharged until the pH is less than 9 oruntil the amount of the basic effluent exceeds the base solutionintroduced into the vessel, and at least a portion of the subsequentaqueous effluent is recycled at least one time through the first vessel.30. The method of claim 29 wherein at least a portion of the subsequentaqueous effluent is recycled as the base solution.
 31. The method ofclaim 30 further adjusting the pH of at least a portion of thesubsequent aqueous effluent to a pH of greater than 9 by adding a baseto the discharged aqueous solution prior to recycling as a portion ofthe base solution.
 32. The method of claim 18 wherein acidic solutioncomprises at least one acid selected from the group consisting ofsulfuric acid, phosphoric acid, hydrochloric acid, nitric acid aceticacid, levulinic acid, lactic acid, formic acid, propionic acid, andmixtures thereof
 33. The method of claim 18 wherein base solutioncomprises at least one base selected from KOH, NaOH or ammonia.
 34. Themethod of claim 18 wherein, in the digestion and/or reaction zone, thetreated cellulosic biomass is contacted with a hydrothermalhydrocatalytic catalyst in the presence of hydrogen and a digestionsolvent thereby producing an intermediate oxygenated product streamcomprising oxygenated hydrocarbons and water; and at least a portion ofthe water is separated and recycled as the aqueous solution.
 35. Themethod of claim 18 wherein, in the digestion and/or reaction zone, thetreated cellulosic biomass is contacted with a hydrothermalhydrocatalytic catalyst in the presence of hydrogen and a digestionsolvent thereby producing an intermediate oxygenated product stream; atleast a portion of the oxygenated intermediate product stream isconverted to a hydrocarbon product stream comprising hydrocarbons andwater; and at least a portion of the water is separated and recycled asthe aqueous solution.
 36. The method of claim 35 wherein, the oxygenatedintermediate product stream comprises oxygenated hydrocarbons and water,and at least a portion of the water is separated and recycled as theaqueous solution.